VOLTAGE COMPENSATION APPARATUS FOR PHOTOVOLTAIC SYSTEM AND PHOTOVOLTAIC SYSTEM

A voltage compensation apparatus for a photovoltaic system and a photovoltaic system are provided. The voltage compensation apparatus includes a current direction limiting module (300) and a compensation power supply (400) connected in series; or only includes a current direction limiting module (300). The current direction limiting module (300) includes at least one limiting device configured to conduct a current in a unidirectional manner. The voltage compensation apparatus is connected between the output terminal of the converter (100) and the ground. The photovoltaic system includes: a photovoltaic array, a converter (100), a transformer (200) and the voltage compensation apparatus. An output terminal of the converter (100) is connected with a primary side of the transformer (200), and an input terminal of the converter (100) is connected with the photovoltaic array. The voltage compensation apparatus is configured to raise or lower a voltage at the output terminal of the converter (100). With the limiting device which conducts a current in a unidirectional manner, the lowest or highest value of the output voltage of the converter (100) can be clamped to the voltage of the compensation power supply (400) or be clamped to the ground.